While touchscreens are undoubtedly popular — over 2.8 billion touchscreens were shipped in 2016 — many computers and electronic devices still use conventional methods of input, such as a keyboard. Not all keyboards work the same, however. There are several different types of keyboard technologies, each of which uses a different method of operation. Below, you’ll discover five of the most common types of keyboards.
#1) Dome Switch
A dome-switch keyboard is a type of flexible keyboard that features a layer of rubber or silicone over metal or polyurethane dome switches. Dome-switch keyboards are often regarded as a hybrid of mechanical and membrane keyboards (see below). Like other types of keyboards, they feature conductive traces. When you press a key, the conductive traces on the two layers meet to complete the circuit.
#2) Membrane
A membrane keyboard is characterized by the use of pressure pads rather than individual and separate keys. They are typically made with a layer of silicone rubber directly below the keys. When you press a key, the conductive traces underneath the key touch the conductive traces on the layer below it.
#3) Capacitive
As the name suggests, a capacitive keyboard is a type of keyboard that works by measuring change of capacitance. There are capacitive touchscreens that use this technology to identify input. When you tap an icon on a capacitive touchscreen, your finger will absorb some of its electrostatic field, resulting in a decrease of capacitance that’s measured as a touch command. Capacitive keyboards use a similar method of operation by leveraging the human body’s conductive properties to identify key presses.
#4) Scissor Switch
Another common type of keyboard is scissor switch. Scissor-switch keyboards feature an interlocking design in which the keys are connected using criss-crossing components that resemble a scissor. When you press a key, the components flex — just like a scissor — so that the key lowers and touches the underlying layer with the conductive traces.
#5) Hall Effect
While not as common as the other types of keyboards listed here, more and more companies are manufacturing and selling hall-effect keyboards. What is a hall-effect keyboard exactly? It’s an innovative type of keyboard that uses magnets and sensors to detect key presses rather than electrical switches and conductive traces. In hall-effect keyboards, each key has a magnet underneath it. When you press a key, the magnet will lower so that it’ can be detected by a sensor. Neither electrical switches nor conductive traces are required with hall-effect keyboards.
